Two Google engineers - one British and one American - have lashed out at the UK and US spy agencies following revelations that the company's internal networks were hacked in order to monitor traffic.

Writing on Google+, Brandon Downey said: "Fuck these guys. I've spent the last ten years of my life trying to keep Google's users safe and secure from the many diverse threats Google faces.

"After spending all that time helping in my tiny way to protect Google - one of the greatest things to arise from the Internet - seeing this, well, it's just a little like coming home from War with Sauron, destroying the One Ring, only to discover the NSA is on the front porch of the Shire chopping down the Party Tree and outsourcing all the hobbit farmers with half-orcs and whips."

Following Downey's outburst, his British security team colleague, Mike Hearn then took to the social network to accuse the NSA and GCHQ of "industrial-scale subversion of the judicial process" in hacking the company's networks.

"I now join him in issuing a giant Fuck You to the people who made these slides. I am not American, I am a Brit, but it's no different - GCHQ turns out to be even worse than the NSA," wrote Hearn.

"The packet capture shown in these new NSA slides shows internal database replication traffic for the anti-hacking system I worked on for over two years.

"In the absence of working law enforcement, we therefore do what Internet engineers have always done - build more secure software. The traffic shown in the slides below is now all encrypted and the work the NSA/GCHQ staff did on understanding it, ruined.

"Thank you Edward Snowden. For me personally, this is the most interesting revelation all summer," he added.